Digital Cancellation of Passive Intermodulation: Method, Complexity and Measurements

This paper addresses digital cancellation of passive intermodulation (PIM) products in simultaneous transmit-receive systems, with specific emphasis on frequency-division duplexing (FDD) based LTE and 5G New Radio (NR) networks. Building on mathematical modeling of the passive intermodulation, a computationally efficient digital cancellation and associated parameter learning solutions are derived and presented. The performance of the method is analyzed through interband carrier aggregation based RF measurements at LTE/NR bands 1 and 3. The measurement results show that the proposed canceller can efficiently cancel the PIM products towards t he receiver noise floor. Additionally, t he proposed canceller is shown to be of substantially lower complexity compared to the reference methods.

[1]  Mikko Valkama,et al.  Digital Cancellation of Passive Intermodulation in FDD Transceivers , 2018, 2018 52nd Asilomar Conference on Signals, Systems, and Computers.

[2]  Peter M. Asbeck,et al.  All-Digital Cancellation Technique to Mitigate Receiver Desensitization in Uplink Carrier Aggregation in Cellular Handsets , 2013, IEEE Transactions on Microwave Theory and Techniques.

[3]  S. Haykin,et al.  Adaptive Filter Theory , 1986 .

[4]  Mikko Valkama,et al.  Digital self-interference cancellation in inter-band carrier aggregation transceivers: Algorithm and digital implementation perspectives , 2017, 2017 IEEE International Workshop on Signal Processing Systems (SiPS).